The goal is to dictate text and commands from an Android device to a PC with a HID interface, any operating system.

For this they use:

An Android application written as a DroidScript http://droidscript.org/ script

An Arduino with HID like leonardo, pro micro, feather etc. https://learn.adafruit.com/adafruit-feather-32u4-bluefruit-le

A JY-MCU Bluetooth device connected to the Arduino for serial communication.

The application on the arduino that processes the words received from the Android.

Instructions:

The hardware is simply the Arduino connected to the JY-MCU Bluetooth across the TX and RX ports of both.

This hardware is connected by usb to the pc, in the same way as it is done to program it.